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BD CARV II Installation and User’s Guide
Figure 3-11
Emission Wheel Screen Default Filter Positions
When in the calibration mode, the checksum for the wheel is calculated and
saved when the BACK button is pressed. If the power is disconnected before the
BACK button is pressed, the checksum will fail upon the next startup and the
default positions will be used. If this happens, the cause is probably a minor
failure of the non-volatile memory and the positions on the filter wheel will have
to be recalibrated. Memory failure is a rare occurrence and does not indicate any
permanent flaws in the instrument. If there is any memory failure at all it most
likely will be with only one of the wheels. Therefore, only one wheel screen will
display the “DEFAULT POSITIONS” text and only this wheel will need to be re-
calibrated.
Instructions for activating the calibration function for the filter wheels and a
screen shot for each screen can be found in the Eight-Position Filter Wheel
Screens on page 39 or the Dichroic Wheel Screen on page 41. Notice that the
calibrated value for the active position on the wheel is displayed when the
calibration function is activated. These values can be read for all positions on all
wheels with one command. All positions on a filter wheel can be written with
another command. If any position is recalibrated outside of the factory, all the
values should be read and stored, either copied by hand during calibration or
read via software and saved as a file. If these new values then need to be restored,
they can either be entered by hand by calibrating each position one at a time, or
written to with a software command. Refer to the software manual for the
imaging software you are using for the syntax and a description of each
command needed to do this.
